Gelastopsis croydonensis Constant, 2026, sp. nov.

Gelastopsis croydonensis sp. nov. urn:lsid:zoobank.org:act: DED84640-173E-4C30-8DF9-FCF2A50F69CE Figs 1–7 Diagnosis The species can be recognized by the following combination of characters: (1) black band of upper portion of frons with incomplete, median, pale yellowish, narrow stripe limited to upper half of black area (Fig. 2B); (2) hind wings narrow (LW/BW = 2.3) with a narrow but distinct anal lobe, and vein A2 reaching to about ⅔ of lobe length (Fig. 2F); (3) anal tube in dorsal view strongly elongate and constricted in middle portion and with apical margin rounded (Fig. 3B); (4) gonostyli in lateral view with anterodorsal process partly covering pygofer, strongly, roundly downcurved and with apex directed ventrad (Fig. 3A). Etymology The species epithet refers to the town of Croydon in Queensland, where the species was collected. Type material Holotype AUSTRALIA • ♂; Australia Qld, Croydon, Diehm’s Lookout; 18°11′20″ S, 142°15′49″ E; 20–21 Mar. 2025; 150 m a.s.l.; J. Constant and L. Semeraro leg.; Leopold III Funds Expedition; QM. Paratypes AUSTRALIA • 2 ♀♀; same data as for holotype; QM • 1 ♂, 3 ♀♀; same data as for holotype; RBINS. Description MEASUREMENTS AND RATIOS. LT: ♂ (n = 2): 6.6 mm (6.4–6.7); ♀ (n = 4): 6.4 mm (6.3–6.5); BV/LV = 3.49; BF/LF = 1.98; LP+LM/BT = 0.66; LTg/BTg = 3.08; LW/BW = 2.27. Male HEAD (Figs 1A–D, 2A–C). Vertex weakly concave, brown with pale median stripe and darker on sides (more so anteriorly), often covered in golden-brown pruinose secretion; margins slightly carinate; anterior and posterior margins curved, subparallel. Dorsal half of frons black with oblique sublateral yellowish line; incomplete, median, pale yellowish, narrow stripe limited to upper half of black area; lower margin of black area bisinuate; two strong, coalescent, wrinkled impressions (carinate dorsally), each bearing central white waxy spot; pale yellowish, transverse band under black zone; ventral half of frons brown with irregular, darker markings, often covered in whitish-yellow pruinose secretion and bearing 2–3 transverse, irregular, darker carinae. Sides of head yellowish, turning brown in upper portion. Clypeus brown with sides blackish and laterodorsal angles yellowish; antennae blackish; scape short; pedicel subcylindrical, barrel-shaped. THORAX (Figs 1A–D, 2A–C). Pro- and mesonotum brown with irregular, weakly darker patches, often covered in golden-brown pruinose secretion; group of obsolete, paler tubercles at each side. Pronotum with anterior margin curved and posterior margin bisinuate. Mesonotum with distinct median and sublateral (peridiscal) carinae, median stopping before scutellum. Tegulae pale brown. TEGMINA (Figs 1A–D, 2E). Costal and sutural margins subparallel; slightly tapering along distal half; costal margin very weakly sinuate; often covered in golden-brown pruinose secretion (more so in anterior portion); dark brown with irregular, paler markings in distal half; apex dark brown with ante-apical, white, transverse stripe; paler costal patch (veins dark brown) before dark brown apical zone; apex sligthly obliquely, roundly truncate. VENATION. ScP+R forking close to base after rather short common stem, ScP+RA and RP running more or less parallel to costal margin; first fork of MP very basal, at level of ScP+RA–RP separation; first fork of CuA slightly before apex of clavus; clavus closed; Pcu and A1 fused at about ¾ of clavus length; Pcu+A1 reaching apical angle of clavus; numerous cells along posterior half of costal margin; numerous cross-veins on apical third delimiting small elongate cells. POSTERIOR WINGS (Fig. 2F). Narrow, about 2.3 × longer than broad, with a narrow but distinct anal lobe, and vein A2 reaching to about ⅔ of lobe length. All main veins visible from base, forked about nodal line, except MP forked before halflength, and forming a few closed cells; transverse veinlets delimiting elongate cells on distal ⅓. LEGS (Figs 1A–D, 2D). Pro- and mesofemora and tibiae yellowish-brown, more or less densely variegated with dark brown; pro- and mesotarsi slightly darker apically; posterior legs yellowish-brown with apex of tibial and tarsal spines darker. Pro- and mesofemora and tibiae dorsoventrally flattened, elongate and slender, tibiae more slender than corresponding femora; metatibiae with 3 lateral and 9 apical spines; first metatarsomere ventrally with darker pad of microsetae at internoapical angle and 9 spines more or less arranged in two rows. Metatibiotarsal formula: (3) 9/9/0. ABDOMEN. Bright red with genital segments brown. MALE TERMINALIA (Figs 3–4). Pygofer (Fig. 3: Py) in lateral view strongly sinuate, rather broad ventrally and tapering towards upper portion; in dorsal view, posterior margin excavate; in ventral view, posterior margin distinctly incurved. Anal tube (Fig. 3A–C, E–F: An) in dorsal view strongly elongate and constricted in middle portion, about 2.1 × as long as broad, with lateral margins strongly diverging in distal portion before rounded apical margin; distinctly grooved medially after anal opening, groove not reaching apical margin; more or less straight, then distinctly downcurved in distal portion in lateral view; row of minute teeth along apical margin; anal opening in basal ¼. Gonostyli (Fig. 3: G) fused on most of length, elongate in lateral and ventral views (distinctly longer than wide) with apex rounded, basally projecting into wide process projecting cephaloventrad, apically pointed (point directed ventrad), and largely covering pygofer in lateral view; in caudal view, gonostyli taken together forming a widely open ‘V’, with lateral portion upcurved. Aedeagus (Fig. 4) mostly membranous with lateral, semicircular, sclerotized process on each side, downcurved in distal portion and with apical hook, articulated to lateroventral process of periandrium; lateroventral process of periandrium with basal apodeme directed cephalad, corpus strongly but shortly projecting ventrad, then distinctly upcurved in lateral view and moderately curved mesad in dorsal view, apex pointed. Distribution and biology The species is currently recorded from a single locality, Croydon in the Gulf of Carpentaria area of Queensland, in the Gulf Plains bioregion (Fig. 7). The specimens were collected in March. They are cryptic when sitting on the branches of their host plant, Acacia holosericea A.Cunn. ex G.Don / A. colei Maslin & L.A.J. Thomson (Fabaceae) in open Eucalyptus L’Her. woodland (Figs 5–6). A specimen was observed at day time, in a trophobiotic interaction with ants collecting the honeydew produced by the planthopper. The ants were identified as Camponotus wiederkehri Forel, 1894 (Hymenoptera: Formicidae: Formicinae) (Fig. 5C–F) and the observed ant specimens belong to different casts; the behaviour of the ants included antennal, palpal and proleg contact/ palpation which are regarded as a way to stimulate honeydew production by the planthopper (Bourgoin et al. 2023).